Ceiling loudspeaker system

ABSTRACT

The present invention comprises a method and apparatus for installing a tile-mounted ceiling speaker that combines the ease of installation of a lay-in speaker system with the visual appearance of a tile-mounted speaker system. In one or more embodiments, the apparatus of the present invention includes a support frame and back box assembly configured for installation on top of a ceiling tile and a loudspeaker cartridge configured to be mounted to the support frame through an appropriately-sized hole in the ceiling tile. In one or more embodiments, the method of the present invention comprises forming an appropriately-sized hole in a ceiling tile, laying an integrated back box and support frame on top of the ceiling tile, connecting wires from an external audio source to terminals provided at the back box, connecting wires provided on the inside of the back box to a loudspeaker cartridge, inserting the loudspeaker cartridge into the hole in the ceiling tile from below, fastening the loudspeaker cartridge to the support frame, and fastening a grille to the loudspeaker cartridge. In one or more embodiments, a variety of interchangeable loudspeaker cartridges having differing loudspeaker configurations are provided. In one or more embodiments, the support frame and back box assembly is configured to allow installation of more than one loudspeaker cartridge. In one or more embodiments, the loudspeaker cartridges are configured for use both with a back box and without back box.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a continuation of U.S. patent applicationSer. No. 13/161,022 filed Jun. 15, 2011, which issued as U.S. Pat. No.8,631,897 on Jan. 21, 2014, which is a continuation in part of U.S.patent application Ser. No. 13/159,801 filed Jun. 14, 2011, which issuedas U.S. Pat. No. 8,286,749 on Oct. 16, 2012, which is a continuation inpart of U.S. patent application Ser. No. 12/795,218 filed Jun. 7, 2010,which issued as U.S. Pat. No. 8,109,360 on Feb. 7, 2012, which is acontinuation in part of U.S. patent application Ser. No. 12/355,730filed Jan. 16, 2009, which issued as U.S. Pat. No. 7,866,438 on Jan. 11,2011, which is a continuation-in-part of U.S. patent application Ser.No. 12/163,929 filed Jun. 27, 2008, which issued as U.S. Pat. No.7,861,825 on Jan. 4, 2011, all of which are incorporated by reference intheir entirety herein.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to a loudspeaker system for mounting in asuspended ceiling comprising a support frame and back box assembly and aremovable speaker cartridge.

(2) Background of the Invention

Suspended ceilings, consisting of ceiling tiles supported by a grid oft-bar frames, are common in business as well as in some residentialenvironments. It is often desired to mount loudspeakers in suspendedceilings to provide for communications and/or entertainment.Consequently, various types of loudspeaker systems have been developedfor installation in suspended ceilings.

One type of prior art ceiling loudspeaker system consists of aloudspeaker mounted to a conventional ceiling tile. A hole is cut in theceiling tile to accommodate the speaker, and the speaker is mounted tothe tile over, in, or adjacent to the hole. The size of speaker that canbe used in this type of loudspeaker system is limited becauseconventional ceiling tiles have limited structural strength and in somecases are rated by the manufacturers as having no structural strength atall. FIG. 1 shows a modification of this type of ceiling loudspeakersystem that adds a support frame that provides additional support forthe loudspeaker. As shown in FIG. 1, the support frame includes supportbars 105 and 110 that extend across the back of a ceiling tile 115 tot-bar frames (such as t-bar frame 120) that support the ceiling tile,and a support ring 125 that is mounted to support bars 105 and 110adjacent to the hole 130 in ceiling tile 115. The speaker is mounted onsupport ring 125 so that some or all of the weight of the speaker issupported by the support bars and ring and not just the speaker tile,allowing a heavier speaker to be used. The speaker can be a singlespeaker or can be a speaker assembly that includes multiple speakers. Afurther modification of this type of ceiling loudspeaker system adds ametal “can” to the back of the speaker assembly that is intended tocomply with fire codes for plenum installations.

An example of a ceiling speaker assembly that includes a back can andthat is intended to be mounted in a ceiling tile using a support framelike that shown in FIG. 1 is the SI 26CT model ceiling speaker sold byExtron Electronics, which is shown in FIG. 2. As shown in FIG. 2, the SI26CT ceiling speaker assembly 200 includes a woofer 205 with a coaxiallymounted tweeter 210 mounted to a speaker frame 215. A metal back can 220is mounted to the back of speaker frame 215 forming a chamber thatencloses the back side of woofer 205. A removable panel in the back ofmetal back can 220 (not shown) provides access for electricalconnections to the speaker unit. A crossover circuit may also be mountedto the rear of woofer 205. Internal speaker wires lead from thecrossover circuit to each of woofer 205 and tweeter 210. To improve theacoustic response, a port 225 is formed in speaker frame 215. Aplurality of mounting doglegs (sometimes referred to herein as “dogs” or“flip dogs”) 230 are attached to the rear of speaker frame 215. To mountspeaker assembly 200 onto a ceiling tile, an appropriate hole is cutinto the ceiling tile. A support frame such as that shown in FIG. 1 isinstalled on top of the ceiling tile. The rear of speaker assembly 200is inserted into the hole in the ceiling tile from the bottom untilspeaker frame 215 is flush against the bottom surface of the ceilingpanel. Mounting dogs 230 are then pivoted such that the ends of theirdoglegs are disposed over the support ring on the back side of theceiling tile, thereby securing speaker assembly 200 to the ceiling tileand support frame.

Another type of ceiling speaker is a “lay-in” ceiling speaker, anembodiment of which is disclosed, for example, in U.S. Pat. No.6,944,312 issued to Mason et al. entitled “Lay-In Ceiling Speaker.” Thelay-in speaker disclosed in Mason et al. is intended to replace anentire ceiling tile. It consists of a speaker mounted to a perforatedmetal grille, which is crimped to a fiberglass back box, forming agenerally rigid loudspeaker assembly that has the same lateraldimensions as a standard ceiling tile and that can be mounted in asuspended ceiling simply by removing an existing ceiling tile andputting the “lay-in” loudspeaker assembly in its place, the edges of the“lay-in” speaker resting on the t-bar support frames of a suspendedceiling in the same manner as a ceiling tile. When installed, the visualappearance of a lay-in speaker is that of a perforated grill having thesize and shape of a ceiling tile.

Although lay-in speakers are easy to install, sometimes the visualappearance of a tile-mounted ceiling speaker is preferred over theappearance of a lay-in speaker. Until now, there has been no ceilingspeaker assembly that combines the ease of installation of a lay-inspeaker with the aesthetics of a tile-mounted ceiling speaker.

BRIEF SUMMARY OF THE INVENTION

The present invention comprises a method and apparatus for installing atile-mounted ceiling speaker that combines the ease of installation of alay-in speaker system with the visual appearance of a tile-mountedspeaker system. In one or more embodiments, the apparatus of the presentinvention includes a support frame and back box assembly configured forinstallation on top of a ceiling tile and a loudspeaker cartridgeconfigured to be mounted to the support frame through anappropriately-sized hole in the ceiling tile. In one or moreembodiments, the method of the present invention comprises forming anappropriately-sized hole in a ceiling tile, laying an integrated backbox and support frame on top of the ceiling tile, connecting wires froman external audio source to terminals provided at the back box,connecting wires provided on the inside of the back box to a loudspeakercartridge, inserting the loudspeaker cartridge into the hole in theceiling tile from below, fastening the loudspeaker cartridge to thesupport frame, and fastening a grille to the loudspeaker cartridge. Inone or more embodiments, a variety of interchangeable loudspeakercartridges having differing loudspeaker configurations are provided. Inone or more embodiments, the support frame and back box assembly isconfigured to allow installation of more than one loudspeaker cartridge.In one or more embodiments, the loudspeaker cartridges are configuredfor use both with a back box and without back box.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be understood and its features made apparentto those skilled in the art by referencing the accompanying drawings.

FIG. 1 is a perspective view of an embodiment of a support frame of theprior art.

FIG. 2 is a perspective view of ceiling speaker assembly of the priorart.

FIG. 3 is an exploded perspective view of an embodiment of a supportframe and back box assembly of the present invention.

FIG. 4 is a rear perspective view of an embodiment of a support frameand back box assembly of the present invention.

FIG. 5 is a front perspective view of an embodiment of a support frameand back box assembly of the present invention.

FIG. 6 is an exploded perspective view of an embodiment of a speakercartridge of the present invention.

FIG. 7 is a rear perspective view of an embodiment of a speakercartridge of the present invention.

FIG. 8 is a front view of an embodiment of a speaker cartridge of thepresent invention.

FIG. 9 is a close up view showing electrical connections for anembodiment of a back box of the present invention.

FIG. 10 is a close up view showing electrical connections for anembodiment of a speaker cartridge of the present invention.

FIGS. 11A-11C show a method of mounting an embodiment of a support frameand back box assembly of the present invention.

FIGS. 12A-12C show a method of mounting an embodiment of a speakercartridge of the present invention.

FIG. 13A is a perspective view of an embodiment of a speaker cartridgeof the present invention mounted in a ceiling tile.

FIG. 13B is a cutaway perspective view of an embodiment of a speakercartridge of the present invention mounted to an embodiment of a supportframe and back box assembly of the present invention.

FIGS. 14A-14C show removable spacer tabs of one or more embodiments ofthe present invention.

FIG. 15 is an exploded view of a “flip dog” assembly of one or moreembodiments of the present invention.

FIGS. 16A-16B show assembled “flip dog” assemblies of one or moreembodiments of the present invention.

FIGS. 17A-17C illustrate a process for engaging a “flip dog” accordingto one or more embodiments of the present invention.

FIGS. 18A-18C show details of a screw hole of a “flip dog” of one ormore embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, numerous specific details are set forth toprovide a more thorough description of the present invention. It will beapparent, however, to one skilled in the art, that the present inventionmay be practiced without these specific details. In other instances,well-known features have not been described in detail so as not toobscure the invention.

FIG. 3 is an exploded view showing components of a support frame andback box assembly 375 of an embodiment of the present invention. In theembodiment of FIG. 3, components of support frame and back box assembly375 include a support frame 300, a back box 305, and an outer shield310.

In the embodiment of FIG. 3, support frame 300 comprises a metal,plastic, or other material or materials formable into the desired shapeand form. In one or more embodiments, support frame 300 is formed as asheet metal stamping. In the embodiment of FIG. 3, support frame 300includes a planar portion 301, an opening 304 (which in one or moreembodiments is surrounded by an inside lip 306), a plurality ofstiffening ribs 303 (which can have any of a desired configuration,including longitudinal ribs parallel to the width or length of supportframe 300, ribs having the general form shown in FIG. 3, or any otherconfiguration, shape and size), and an outside lip 302. In one or moreembodiments, outside lip is initially formed at an approximately rightangle to planar portion 301. In one or more embodiments, support frame300 is formed from a sheet of material. In alternative embodiments,stiffening ribs 303 and/or outside lip 302 and/or inside lip 306 may notbe integrally formed with planar portion 301, but may compriseseparately formed components that are affixed to planar portion 301 toform support frame 300. In the embodiment of FIG. 3, support frame 300comprises a single centrally-located round opening 304 for receiving aspeaker or a speaker cartridge. In one or more other embodiments,support frame 300 may comprise two or more openings for receivingspeakers or speaker cartridges. The openings may have the same ordifferent shapes (round, rectangular or other) and sizes, and may eachbe located anywhere in speaker frame 300. Further, planar portion ofspeaker frame 300 need not be formed from a single piece of material,but may be assembled from separately formed pieces. Further, althoughspeaker frame 300 is shown as having a generally rectangular shape, anyother desired shape can be used.

In the embodiment of FIG. 3, back box 305 comprises a raised portion 309and an edge portion 308. In one or more embodiments, edge portion 308comprises a plurality of spacer tabs 307 that allow the overall lengthof back box 305 to be adjusted so that support frame and back boxassembly 375 can be used with a plurality of ceiling t-bar spacings. Inone or more embodiments, the overall length of support frame and backbox assembly 375 with spacer tabs 307 intact is approximately 2 feet,which is a standard width for ceiling tiles in the United States. In oneor more embodiments, with spacer tabs 307 removed (for example bybreaking off with a tool such as a pair of pliers), the overall lengthof support frame and back box assembly 375 is approximately 600 mm,which is a standard width for ceiling tiles in some European countries.FIGS. 14A-14C illustrate how spacer tabs 307 may be removed (for examplewith pliers 1401 as shown in FIG. 14B) to create two different overalllengths for support frame and back box assembly 375. Although spacertabs 307 are shown as all having the same length and disposed along onlyone side of support frame and back box assembly 375, in one or morealternative embodiments, spacer tabs may be included on other sides.Further, two or more sets of spacer tabs having different lengths may beused along one or more sides, providing additional discrete, selectablevariations of overall lengths and/or widths for support frame and backbox assembly 375 depending on which tabs are removed. In one or moreembodiments, spacer tabs are scored or notched to facilitate removal ofthe tabs.

In one or more embodiments, back box 305 is formed from high molecularweight polyethylene (“HMWPE”), though back box 305 can be formed fromany other plastic, metal, or composite material or materials. In one ormore embodiments, back box 305 comprises a recessed portion 314 that isconfigured to accommodate a stiffening plate 320 to provide additionalstructural rigidity. In one or more embodiments, stiffening plate 320 ismade from a relatively stiff material, such as medium density fiberboard(“MDF”). The use of stiffening plate 320 allows support frame and backbox assembly 375 to have significant rigidity (which is desirable forimproved acoustical response) yet be relatively light in weight.Stiffening plate 320 also improves bass response by adding materialdensity to back box 305 and reducing deflection of back box 305. In oneor more embodiments, back box 305 comprises a recessed electricalcompartment 311 that includes electrical terminals 340 for makingexternal electrical connections.

In the embodiment of FIG. 3, outer shield 310 is configured to bemountable over back box 305 such that the inside surface of outer shield310 conforms generally to the outside surface of back box 305. In one ormore embodiments, outer shield 310 includes a raised portion 360 and anedge portion 365. In one or more embodiments, outer shield 310 is formedfrom materials as is known in the art that provide fire and heatresistance in conformity with applicable building codes. In one or moreembodiments, outer shield 310 comprises a composite constructioncomprising an inner mineral fiber or fiberglass shell and an outer metalfoil layer. In one or more embodiments, outer shield 310 conforms to theUnderwriters' Laboratories UL2043 rating. In one or more embodiments,outer shield 310 includes an opening 334 that is configured to provideaccess to electrical compartment 311 of back box 305 when outer shield310 is assembled to back box 305 and support frame 300. In one or moreembodiments, outer shield 310 is provided with a pair of plates 335comprising threaded holes that can be used to mount a cover plate 350over opening 334 using fasteners 355.

In the embodiment of FIG. 3, support frame 300, back box 305, stiffeningplate 320 and outer shield 315 are assembled together to form an anembodiment of a support frame and back box assembly of the invention. Inone or more embodiments, stiffening plate 320 is fastened to back box309 using a plurality of screws 330. Back box 305 is fastened to supportframe 300 and stiffening plate 345 using bolts 325, spacers 315 andbarrel nuts 345. In one or more embodiments, when assembled, thecomponents work together to form an assembly that has a rigidity greaterthan the rigidity of the individual components. In one or moreembodiments, spacers 315 act as stiffeners that, together with bolts 325and barrel nuts 345, mechanically tie support frame 300 and back box 305together, reducing any bellows effect of the enclosure formed by supportframe 300 and back box 305. In one or more embodiments, spacers 315 areformed from a plastic, a metal, or any other material or combination ofmaterials.

In one or more embodiments, outside lip of support frame 300 includesopenings 313 through which spacer tabs 307 of back box 305 protrude whenback box 305 is mounted to support frame 300.

In the embodiment of FIG. 3, after back box 305 is assembled to supportframe 300, outer shield 310 is placed over back box 305 such that edgeportion 365 of outer shield 310 rests on edge portion 308 of back box305. In one or more embodiments, outside lip of support frame 300 isthereafter folded over edge portion 365 of outer shield 310 such thatoutside lip holds outer shield 310 in place, as shown in FIG. 4, whichshows a top view of an embodiment of a resulting support frame and backbox assembly 375 of the invention. A bottom view of support frame andback box assembly 375 is shown in FIG. 5. In one or more embodiments,additional or other fastening methods and/or fasteners may be used tofasten support frame 300 and/or back box 305 to outer shield 310 as willbe known to those of skill in the art. For example, in one or moreembodiments, spring-loaded or folded clips may be used to hold outershield 310 to support frame 300 and back box 305.

An embodiment of a speaker cartridge 600 of the invention which may beused independently of or with a support frame and back box assembly suchas support frame and back box assembly 375 is shown in FIGS. 6, 7 and 8.FIG. 6 is an exploded view showing components of an embodiment ofspeaker cartridge 600. FIGS. 7 and 8 are top and bottom views,respectively, of embodiments of an assembled speaker cartridge 600.

In the embodiment of FIG. 6, speaker cartridge 600 comprises a cartridgeframe 601 to which various components are mounted. In one or moreembodiments, cartridge frame 601 is molded from a plastic, cast from ametal, or formed in any other manner as will be known by those of skillin the art. In one or more embodiments, cartridge frame 601 is moldedfrom HMWPE. In one or more embodiments, cartridge frame 601 is formed tofit into opening 304 of support frame 300. In one or more embodiments,cartridge frame 601 includes a flange 602. In one or more embodiments,cartridge frame 601 provides mounting locations for components that areintended to be mounted to cartridge frame 601. In the embodiment of FIG.6, components mounted to cartridge frame 601 include a speaker 610, atweeter 615, a tweeter bracket 605, a transformer 624, a switch 614, acrossover circuit board 624, and a plurality of “flip dog” attachmentclips each comprising a flip dog base 618 (which may, for example, beintegrally formed with cartridge frame 601), rotatable flip dog 620 anda flip top cap 622. In one or more embodiments, speaker 610 is amidrange speaker or a woofer. In one or more embodiments, transformer624 is configured to match an incoming audio signal to the signalrequirements of speaker 610. In one or more embodiments, transformer 624has multiple taps that can be selected by switch 614 so that speakercartridge 600 can be used with a variety of input signal configurations.

In the embodiment of FIG. 6, crossover circuit board 624 includes aconventional crossover circuit that divides the incoming audio intoprimarily lower frequency signals that are sent to speaker 610 andprimarily higher frequency signals that are sent to tweeter 615, as isknown in the art.

FIG. 7 shows how components are assembled to cartridge frame 601 in oneor more embodiments of the invention. In the embodiment shown in FIG. 7,a portion of cartridge frame 601 that is configured to fit withinopening 304 of support frame 300 has an inner perimeter 712 that has adiameter equal to or less than the diameter of opening 304. Flange 602extends outwards from perimeter 712 to an outer perimeter 710 that has adiameter greater than the diameter of opening 304 of support frame 300.In the embodiment of FIG. 6, flip dogs 620 are rotatably mounted to flipdog bases 618 such that legs 706 of flip dogs 620 can be rotated from aninward position in which they do not extend beyond inner perimeter 712and can therefore be inserted into opening 304 of support frame 300 toan outward position in which they extend beyond inner perimeter 712 soas to extend over the perimeter of opening 304 so as to hold speakercartridge 600 in place adjacent to support frame 300 when speakercartridge 600 is assembled to support frame and back box assembly 375.In one or more embodiments, flip dogs 620 and flip dog bases 618 areconfigured such that the rotational position of flip dogs 620 can bemanipulated from the bottom side of cartridge frame 601, for example byuse of a tool such as a screwdriver. In one or more embodiments, switch614 is also configured so as to allow operation of switch 614 from thebottom of cartridge frame 601.

In the embodiment of FIG. 7, cartridge frame 601 includes a port 703, aremovable port cover 612, and a port cover storage location 702. Whenmounted to a support frame and back box assembly such as support frameand back box assembly 375, port cover 612 may be removed and stored inport cover storage location 702 so that port 703 functions like aconventional speaker port, providing a path between the outside andinside of the speaker enclosure formed by the combination of speakercartridge 600 and support frame and back box assembly 375. In one ormore embodiments, leaving port 703 covered provides better audioresponse if speaker cartridge 600 is mounted in a ceiling tile orotherwise used in a manner in which the rear of speaker cartridge 600 isnot enclosed by a back box or other housing.

FIG. 8 shows a bottom view of one or more embodiments of speakercartridge 600. In the embodiment of FIG. 8, tweeter bracket 605 has beenmounted to cartridge frame 601, for example by engaging tabs at the endsof the legs of tweeter bracket 605 with mating slots in cartridge frame601. In one or more embodiments, tweeter bracket 605 allows differenttweeters to be used with speaker cartridge 600. In one or moreembodiments, different tweeter brackets 605 may be interchangeably usedwith speaker cartridge 600. In one or more embodiments, tweeter brackets605 may be configured to provide various assembled locations for tweeter615 with respect to speaker 610, allowing the assembled location of aparticular tweeter 615 to be configured to provide a desired acousticalinteraction with speaker 610. In the embodiment of FIG. 8, cartridgeframe 601 includes orifices 802 that provide access to flip dogs 620with an appropriate tool, such as, for example, a screwdriver, that canbe used to rotate flip dogs 620 from a retracted position (in which thelegs 706 do not interfere with insertion of speaker cartridge 600 intoopening 304 of support frame 300) to an extended position (in which legs706 extend beyond opening 304 of support frame 300). In one or moreembodiments, cartridge frame 601 also includes an opening 805 thatprovides access to switch 614.

FIGS. 15 to 18 show details of a flip dog assembly 1500 of one or moreembodiments of the invention. In the embodiment shown in FIG. 15,components of flip dog assembly 1500 include bottom screw 1510, flip dogbase 618 (which may be integrally formed with cartridge frame 601),spring 1501, flip dog 620 (which includes leg 706), flip dog cap 622,and cap screws 1505. Flip dog base 618 includes a bore 1511 and aninclined surface 1512 that together with inclined surface 1513 of flipdog cap 622 forms a guide passage for leg 706 of flip dog 620 asdiscussed in greater detail with respect to FIGS. 16A and 16B below.

In one or more embodiments, flip dog assembly 1500 may be assembled byinserting spring 1501 and flip dog 620 in bore 1511 of flip dog base618, placing flip dog cap 622 over flip dog 620 such that the top 1522of flip dog 620 engages bore 1515 of flip dog cap 622, and fasteningflip dog cap 622 to flip dog base 618 using cap screws 1505. Bottomscrew 1510 can then be inserted through the bottom of flip dog base 618through spring 1501 (which is now partially compressed) and partiallyscrewed into the bottom of flip dog 620, as described in greater detailbelow. The resulting flip dog assembly 1500 is shown in FIGS. 16A and16B

As shown in FIGS. 16A and 16B, in one or more embodiments, flip dog cap622 includes a notch 1517 that maintains leg 706 in its retractedposition while speaker cartridge 600 is being inserted into a mountinghole (e.g. in a ceiling tile or in a support frame, such as supportframe 300 of support frame and back box assembly 375). Leg 706 ispressed upwards into notch 1517 by the upwards bias of spring 1501.

FIGS. 17A-17C show how leg 706 is moved from its retracted position asshown in FIGS. 16A and 16B to its engaged position as shown in FIG. 17C.The movement is accomplished by screwing bottom screw 1510 into thebottom of flip dog 620 such that flip dog 620 is pulled downwards intoflip dog base 618 though guide passage 1610 formed by flip dog cap 622and flip dog base 618. As shown in FIGS. 17A-17C, as flip dog 620 ispulled downwards by bottom screw 1510, the configuration of passage 1610causes leg 706 first to disengage from notch 1517 and then to rotateoutwards into its extended position as shown in FIG. 17B. Furthertightening of bottom screw 1510 draws leg 706 further downwards into itsfully engaged position, as shown in FIG. 17C.

FIGS. 18A and 18B show a configuration of a screw bore 1801 in flip dog620 in one or more embodiments of the invention. As shown in FIG. 18A,screw bore 1801 includes a guide portion 1810 that has a diameterapproximately the same diameter as the outside diameter of the threadsof screw 1510 and a screw engagement portion 1805 that has a diameterthat is less than the outside diameter of the threads of screw 1510.Guide portion 1810 aligns bottom screw 1510 with screw engagementportion 1805 as screw 1510 is inserted into screw bore 1810, preventingscrew 1510 from becoming misaligned as screw 1510 is screwed intoengagement portion 1805.

Although cartridge frame 601 is shown in the embodiment of FIG. 8 tohave a generally round shape that generally matches the shape of opening304 in support frame 300, in one or more embodiments, other shapes forboth cartridge frame 601 and opening 304 can be used. Further, althoughcartridge frame 601 of FIG. 8 is configured for a single woofer ormidrange speaker and a single tweeter, in one or more other embodiments,cartridge frame 601 can be configured for multiple midrangespeakers/woofers and/or multiple tweeters.

FIG. 9 shows how external wiring is connected to electrical terminals340 of support frame and back box assembly 375 in one or moreembodiments of the invention. In the embodiment shown in FIG. 9, a pairof external electrical leads 915 are fed through a conduit header 905mounted to cover plate 350 (which has been removed to allow access) andattached to Euro-type screw electrical terminals 340 in a recessedelectrical compartment 311 formed in back box 305 and accessible throughopening 334 of outer shield 310. A pair of internal electrical leads 920lead from screw electrical terminals 340 into the interior of back box305.

FIG. 10 shows how internal leads 920 are connected to crossover circuitboard 624 in one or more embodiments of the invention. In the embodimentof FIG. 10, internal leads 920 (which may, for example, be connected toexternal leads 915 via electrical terminals 340) are connected to anelectrical connector 1010 (for example a Molex connector) that isconfigured to removably mate with a mating electrical connector 624 (forexample a Molex connector) connected to crossover circuit board 624.Using removable mating connectors for connecting internal leads 920 tocrossover circuit board 624 facilitates installing speaker cartridge 600and support frame and back box assembly 375 into a suspended ceiling, asdescribed below.

FIGS. 11A-11C illustrate steps for installing a support frame and backbox assembly 375 into a suspended ceiling according to one or moreembodiments of the invention. FIG. 11A shows a support frame and backbox assembly 375 placed into a desired position in a grid of t-barceiling tile support bars 1105. FIG. 11B shows a ceiling tile 1110placed into the same position in grid 1105 in which support frame andback box assembly 375 is shown in FIG. 11A. In FIG. 11B, an opening 1120has been cut in ceiling tile 1110 that corresponds to the location ofopening 340 of support frame 300 of support frame and back box assembly375 of FIG. 11A. FIG. 11C shows support frame and back box assembly 375placed in position on top of ceiling tile 1110.

FIGS. 12A-12C illustrate steps for installing a speaker cartridge 600into an opening 1120 of a ceiling tile 1110 with or without a supportframe and back box assembly 375 according to one or more embodiments ofthe invention. FIG. 12A is a bottom view of a ceiling tile 1110 with anopening 1120. A support frame and back box assembly 375 may or may nothave been placed on top of ceiling tile 1110. If a support frame andback box assembly 375 has been placed on top of ceiling tile 1110,opening 304 of support frame 300 will be in the same location as opening1120 of ceiling tile 1110.

FIG. 12B shows how electrical leads 1015 are fed through opening 1120 ofceiling tile 1110 and attached to speaker cartridge 600, for example byusing connectors such as connectors 1005 and 1010 of the embodiment ofFIG. 10. If a support frame and back box assembly 375 has been placed ontop of ceiling tile 1110, electrical leads 1015 may for example beinternal electrical leads 920 of the embodiment of FIG. 9.

FIG. 12C shows how a screwdriver 1210 may be used to secure speakercartridge 600 to ceiling tile 1110 (if no support frame and back boxassembly 375 is present) or to ceiling tile 1110 and support frame 300of support frame and back box assembly 375 (if a support frame and backbox assembly 375 is present) by tightening bottom screw 1510, therebymoving flip dogs 620 from their retracted to engaged positions viaaccess passages provided on the bottom side of speaker cartridge 600such as, for example, orifices 802 of the embodiment of FIG. 8. Afterspeaker cartridge 600 has been secured to ceiling tile 1110 and/orsupport frame and back box assembly 375, a detachable decorative grille1310 may be attached to the bottom of speaker cartridge 600, as shown,for example, in FIG. 13A. In FIG. 13B, ceiling tile 1110 is renderedinvisible to show the assembly of speaker cartridge 600 to support frameand back box assembly 375 in one or more embodiments of the invention.

Thus one or more embodiments of a ceiling speaker system comprising asupport frame and back box assembly and a mating speaker cartridge hasbeen disclosed. An advantage of the disclosed invention is that itallows a division of labor in installing a ceiling speaker system thatcorresponds to a common division of labor in building trades. An exampleof such a division of labor is between a building contractor thatinstalls a suspended ceiling, an electrician that installs buildingwires, and an audio/video system installer that installs speakers. Usingone or more embodiments of the invention, a building contractor canplace a support frame and back box assembly on top of a ceiling tile andcut an appropriate opening in the ceiling tile. The contractor typicallywould also install safety support wires (which may be required byapplicable building and/or safety codes for seismic or other reasons)from the support frame and back box assembly to a support structure,such as a ceiling joist. An electrician can run external wiring to theelectrical terminals of the back box of the support frame and back boxassembly. After the support frame and back box assembly is in place inthe ceiling and the external electrical wires have been attached, anaudio/video system installer can attach the internal leads of thesupport frame and back box assembly to a speaker cartridge, and installthe speaker cartridge into the ceiling tile and support frame and backbox assembly from below.

A further advantage of the invention is that the support frame and backbox assembly of the one or more embodiments of the invention forms aloudspeaker enclosure that has a relatively large volume but a lowprofile that allows installation in ceilings that have limited verticalclearance above the ceiling tiles. A further advantage is that in one ormore embodiments, the fire-resistant back box encloses the entire rearof the speaker cartridge assembly, including its mounting hardware,which remain exposed in prior art ceiling speaker systems (such as, forinstance, flip dogs 230 of the prior art ceiling speaker shown in FIG. 2that are not enclosed by back can 230 and that could therefore besubjected directly to fire).

Although the present invention has been described with respect tocertain specific embodiments, it will be clear to those skilled in theart that the inventive features of the present invention are applicableto other embodiments as well, all of which are intended to fall withinthe scope of the present invention. For example, although certainfastening methods and fasteners (e.g. screws) are disclosed forassembling various components of the invention, any other fasteningmethods and/or fasteners may be used (such as, for example, adhesives).Further, certain features of the invention can be used with other itemsother than a ceiling speaker. For example, the removable spacing tabs ofthe invention may be used with other items for which it would be usefulto vary an overall dimension by discrete amounts, including items to bemounted in suspended ceilings, and elsewhere. Similarly, the flip dogassembly of the present invention can be used with other items that areintended to be mounted in holes in ceilings, walls, desktops, andelsewhere. Other variations of and uses for various aspects of thepresent invention will be apparent to those of skill in the art.

1. A loudspeaker assembly comprising: a loudspeaker housing comprising agenerally planar support frame having a top surface and a bottom surfaceand a back box resting upon said top surface of said support frame suchthat said support frame and said back box define an interior volume ofsaid loudspeaker housing, said support frame comprising an opening; aremovable loudspeaker cartridge comprising at least one loudspeakerdisposed in said opening of said support frame, said removableloudspeaker cartridge comprising flip dogs engaged with said top surfaceof said support frame adjacent to said opening, said flip dogs beingdisposed in said interior volume of said loudspeaker housing.
 2. Theloudspeaker assembly of claim 1 wherein said back box comprises an edgethat rests upon said top surface of said support frame.
 3. Theloudspeaker assembly of claim 2 wherein said edge of said back boxcomprises a plurality of permanently removable tabs that provide a firstdimension for said back box when said tabs have not been removed and asecond dimension for said back box when said tabs have been removed. 4.The loudspeaker assembly of claim 3 wherein said first dimension is afirst standard width of a ceiling tile and said second dimensioncomprises a second standard width of a ceiling tile different from saidfirst standard width.
 5. The loudspeaker assembly of claim 1 whereinsaid support frame comprises at least one stiffening rib.
 6. Theloudspeaker assembly of claim 5 wherein said back box comprises astiffening plate.
 7. The loudspeaker assembly of claim 3 wherein saidsupport frame comprises a folded edge and wherein said removable tabs ofsaid back box extend through corresponding openings in said folded edgeof said support frame.
 8. The loudspeaker assembly of claim 1 furthercomprising a separate fire resistant outer shield adjacent to said backbox.
 9. The loudspeaker assembly of claim 6 further comprising aseparate fire resistant outer shield adjacent to said back box.
 10. Theloudspeaker assembly of claim 1 wherein said removable loudspeakercartridge comprises a plurality of loudspeakers.
 11. The loudspeakerassembly of claim 10 wherein said plurality of loudspeakers comprises atleast one tweeter.
 12. The loudspeaker assembly of claim 11 wherein saidremovable loudspeaker cartridge comprises crossover circuitry.
 13. Theloudspeaker assembly of claim 1 wherein said removable loudspeakercartridge comprises a transformer with multiple taps.
 14. Theloudspeaker assembly of claim 13 wherein said removable loudspeakercartridge comprises a switch electrically connected to said multipletaps of said transformer.